There were tumultuous scenes as Ukraine's newly-elected parliament gathered for its first meeting on 12 December. The rostrum was besieged, and MPs traded blows next to the speaker's seat.

With no consensus in sight, fist-fights continued the next day, too. What were the people's deputies fighting over?

Trouble started even before the first meeting began. Two MPs, Tabalov father and son, were physically blocked from entering the chamber as opposition deputies accused them of betrayal and joining pro-government parties.

They had to flee from ridicule and flying fists as outrage grew against the defections, a long-established and deeply controversial practice among Ukrainian MPs.

In previous parliaments, many deputies joined their opponents, mostly from pro-government factions, prompting allegations of bribery and intimidation. Such party-hoppers have become derogatively known as "tushky", or "carcasses" in Ukrainian.

'Button-pushers'

As parliamentary proceedings got under way, scuffles continued, too. They focused on alleged breaches of procedure such as proxy voting, which is actually another common practice in the Ukrainian parliament.

Despite a constitutional requirement - recently reinforced by an act of parliament - for each MP to vote personally, some use the electronic voting system to cast votes on their colleagues' behalf even if they are not physically present.

The practice has earned Ukrainian MPs the derisory moniker of "button-pushers".

Scuffles are not unique to the newly-elected assembly. The previous parliament was also plagued by conflict, often resulting in legislative paralysis.

MPs sustained bruises and broken ribs, microphones got pulled out of their sockets and the electronic voting system was damaged over issues like the status of the Russian language and the jailing of former Prime Minister Yulia Tymoshenko.

In the current parliament, another ingredient has been added to the explosive mix - the right-wing Freedom party, which won seats for the first time. Some of its members have solid street credentials, and they have made it very clear they are determined to take on Russian-speaking tycoons from the east, as well as the Communists.

World heavyweight boxing champion Vitali Klitschko, who is now also an MP, has stayed out of the fray so far.

'Do as the law says'

So why can't Ukrainian MPs resolve their differences in a more parliamentary way, without resorting to violence? The trouble-makers say there is no other way of fighting injustice when laws are ignored and rules are broken.

"There is no law saying it is OK to block parliament, but there is also no law saying it is OK to violate the constitution," said Arseniy Yatsenyuk, the leader of parliament's largest opposition faction Fatherland. "Do as the law says and this parliament can start working again."

Some also say that there are few legal ways of dealing with MPs who decide to switch sides once making it into parliament. "There are different mechanisms for holding MPs to account," argues Rostyslav Pavlenko from Mr Klitschko's Udar party, "but some of them have been cancelled."

But the ruling Party of Regions rejects accusations of not playing by the book and says the opposition is deliberately disruptive.

"True to their manner, they are doing all they can to destabilise the situation and block the national parliament," the party said in a statement.

"It is time they realised that they are in a European country's parliament, not in a jungle."

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